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P Hermanek

Publications and source records attributed to P Hermanek.

At least 37 records · Page 2Linked to original sources
PubMed2000

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Journal Article↗
PubMed2000

Role of the surgeon as a variable in the treatment of rectal cancer.

Increasingly, data are being accumulated on the influence of intersurgeon variability on outcome after curative surgical treatment of rectal carcinoma. Thus, today the individual surgeon has to be considered as an independent factor influencing locoregional recurrence, as well as survival rates. In general, higher local control and survival can be expected for specialized colorectal surgeons. There are no clear correlations between surgical volume and outcome. Interinstitutional variability in treatment results reflects intersurgeon variability, but analysis is generally more difficult because of a lack of homogeneity with respect to different confounding factors. There are several factors in surgical technique that are important for long-term outcome. Of greatest apparent importance is the adequacy of mesorectal excision (for carcinomas of the middle and lower third, total mesorectal excision; for carcinomas of the upper third, mesorectal excision down to a mesorectal plane 5 cm distal to the gross tumor margin detected by the surgeon in situ). Furthermore, intraoperative local tumor spillage (tumor perforation during mobilization, incision into the tumor), en bloc resection technique, skill, and the extent of regional lymphadenectomy may influence outcome. For quality assurance, detailed operative reports are required, as well as histopathology examinations concerning indicators of surgical oncologic quality discernable from the resection specimens. In future clinical trials of multimodal treatment of rectal cancer, quality assurance of surgery and pathology is necessary for consideration of the surgeon and surgical technique prognostic factors.

Colorectal Surgery↗
PubMed2000

[Lymph nodes and malignant tumors].

The planning of locoregional tumor therapy (radical surgical resection, curative radiotherapy) is based on the knowledge of locoregional tumor spread, in particular lymph node metastasis. In general, lymphatic spread follows anatomic rules, skipping of nodes is observed maximally in 3%. According to tumor site, uni- or multidirectional lymph drainage is found. In some tumors (carcinoma of penis, malignant melanoma, breast carcinoma) the concept of detection and examination of sentinel node increasingly is of importance. Lymph node metastasis is to be distinguished from the finding of isolated tumor cells in the sinus of lymph nodes (tumor cell emboli). A definite diagnosis of lymph node metastasis requires a careful histopathologic examination. The incidence of regional lymph node metastasis predominantly depends on tumor type, histological grade of differentiation, lymphatic invasion and depth of invasion/tumor size/tumor volume. A careful histopathologic examination of tumor resection specimens in regard of lymph node metastasis is important for indication to additional postoperative treatment, estimation of prognosis and analysis of treatment results. Adequate quality assurance is necessary.

Humans↗
PubMed2000

The German experience: the surgeon as a prognostic factor in colon and rectal cancer surgery.

The data of the German prospective multicenter study of the Study Group for Colo-Rectal Carcinoma (SGCRC) were analyzed by uni- and multivariate methods with regard to surgeon-related prognostic factors. The parameters were frequency of intraoperative local tumor spillage, surgical volume, and department and surgical quality group. The results obtained from the data of the SGCRC implicate consequences for analyses and comparisons of therapy results and studies on adjuvant therapy in colon and rectal cancer. All identified prognostic factors must be regarded and respectively considered in study designs. Colon and rectal cancer patients must also be distinguished and separate analyses are necessary for these.

Aged↗
PubMed1999

International Union Against Cancer. Classification of isolated tumor cells and micrometastasis.

BACKGROUND: Findings of isolated (disseminated or circulating) tumor cells (ITC) by immunocytochemistry and molecular pathology methods have led to varied interpretations and different applications of the TNM system. METHODS: An analysis of the relevant literature was undertaken. In addition, optional proposals for the classification of ITC, micrometastasis, and cytologic results in pleural and peritoneal washings are presented. RESULTS: Immunocytochemistry has a lower false-positive rate than nonmorphologic methods such as flow cytometry or the polymerase chain reaction; therefore the method(s) used always should be recorded. At the current time, the independent prognostic significance of ITC in regional lymph nodes and in the general circulation (blood, bone marrow, and other distant sites) is difficult to assess. To enable comparisons of treatment results and to avoid variation in staging, a finding of ITC should not be considered in the TNM and residual tumor (R) classifications, at least not at the current time. However, for future evaluation of their prognostic significance, the respective findings should be documented according to uniform criteria. CONCLUSIONS: ITC should be distinguished from micrometastasis. To investigate the independent prognostic significance of ITC and of positive lavage cytology, uniform data collection according to the proposed coding schema is recommended.

Ascitic Fluid↗
PubMed1999

Impact of surgeon's technique on outcome after treatment of rectal carcinoma.

PURPOSE: The aim of this study was to analyze the impact of institutions and individual surgeons on long-term prognosis after curative resection of rectal carcinoma. METHODS: We used univariate and multivariate analysis of data from a German prospective, multicenter, patient-care evaluation study. RESULTS: The locoregional recurrence rates and the observed and cancer-related survival rates showed a considerable interinstitutional and intersurgeon variability. Multivariate analysis confirmed the institution and the individual surgeon as significant independent factors influencing locoregional recurrence and survival. There was a statistically highly significant correlation between the rate of locoregional recurrence and survival rate. CONCLUSIONS: The surgeon's technique and skill has to focus on prevention of locoregional recurrence to achieve good long-term outcome after curative resection for rectal carcinoma. New clinical trials on adjuvant treatment have to include quality assurance for surgery and pathology and documentation of the surgeon (as local code).

Carcinoma↗
PubMed1999

[Comparative study of oncological outcome quality in colorectal carcinoma--ranking by surrogate endpoint?].

The data of the German Prospective Multicenter Study of the Study Group Colorectal Carcinoma (SGCRC) were analyzed with regard to interinstitutional differences in 5-year survival by statistical methods adequate for ranking and observing anonymity. Furthermore, possible so-called surrogate endpoints that allow an assessment of definite outcome after surgical treatment earlier than after 5 years were also analyzed. This requires a separate analysis for rectal and colon carcinoma patients. For rectal carcinoma, the combination of the frequency of local tumor cell spillage during tumor resection (iatrogenous tumor perforation and/or incision into or through tumor tissue) and the rate of locoregional recurrences (within 2 years after surgery) could be demonstrated as reliable surrogate endpoint. For colon carcinoma, no reliable surrogate endpoint could be found. Surgical morbidity is not an indicator of definite outcome. A very low rate of surgical mortality does not ensure satisfactory long-term results in colorectal cancer surgery.

Clinical Competence↗
PubMed1999

Prognostic factor research in oncology.

The prognosis of solid tumors is predominantly influenced by the anatomic extent before and after initial treatment. It is defined by the TNM/pTNM system and the residual tumor (R) classification as internationally agreed on and published by the International Union Against Cancer (UICC). However, there are several independent factors effective in prognosis in addition to TNM and R. Their identification is the first objective in prognostic factor research. Correctly applied multivariate methods appropriate for the specific situation play a key role. Cooperation between clinical oncologists and experienced medical statisticians is indispensable. Putative new prognostic factors have to be carefully evaluated before they can be accepted for general use in clinical oncology. In the future, we have to focus on the development of prognostic systems. Such systems integrate multiple independent prognostic factors with present staging (TNM, R) to improve the assessment of prognosis.

Humans↗
PubMed1999

[Development of standards and guidelines by the German Cancer Society].

Since 1993, the German Cancer Society is working on interdisciplinary standards and short guidelines for diagnosis and treatment of malignant diseases. They are developed by interdisciplinary groups of experts and by coordination with the involved medical scientific societies and several coopted partners, in particular the Scientific Advisory Board of Deutsche Krebshilfe and the Working Group of German Cancer Centers. Standard operating procedures for the development and continuous actualization and improvement are observed. Standards and guidelines are published in the book series "Quality Assurance in Oncology", in several medical journals and electronically in the world wide web.

Germany↗
PubMed1998

Classification of regional lymph node metastasis from gastric carcinoma. German Gastric Cancer Study Group.

BACKGROUND: Classification of lymph node metastasis from gastric carcinoma was based on the localization (International Union Against Cancer/American Joint Committee on Cancer [UICC/AJCC] 1992). The authors analyzed the data of the German Gastric Cancer Study (GGCS) to determine whether the number of involved lymph nodes related to the prognosis independent of their anatomic localization (UICC/AJCC 1997). METHODS: For 477 patients of the GGCS resected for cure (UICC/AJCC R0 resection) who had involved regional lymph nodes and no evidence of distant metastases, the 1992 UICC/AJCC classification was compared with the new UICC/AJCC classification (1997) based on the number of involved lymph nodes (ILN). RESULTS: Two hundred fifty-eight patients (54.1%) had 1-6 ILN, 137 patients (28.7%) had 7-15, and 82 patients (17.2%) had more than 15. When the 1992 and 1997 UICC/AJCC classifications were compared, the prognosis of patients classified as pN1 (n = 187) in the 1992 pN classification was homogeneous, whereas there was a marked lack of homogeneity among the patients classified as pN2 (n = 290). For 103 of 290 patients with 1-6 ILN, the prognosis appeared to be more favorable (5-year survival rate, 45.5%), whereas 137 of 290 patients with 7-15 ILN had an intermediate prognosis (5-year survival rate, 29.7%). Eighty-two of 290 patients had a dismal prognosis, with a 5-year survival rate of 10.4%. There was a highly significant difference in survival (P < 0.0001). Within the groups with 1-6, 7-15, and more than 15 ILN, the localization of ILN did not significantly alter the prognosis. CONCLUSIONS: The UICC/AJCC classification based on the number of involved regional lymph nodes allows for an estimation of prognosis superior to the 1992 classification. In addition, the new classification can now be applied without methodologic problems and seems more reproducible.

Carcinoma↗
PubMed1998

Pathology and biology of pancreatic ductal adenocarcinoma.

INTRODUCTION: Ductal adenocarcinoma of the pancreas is a highly aggressive tumor with early local spread beyond the pancreas, predominantly to the retroperitoneum, but also with invasion of adjacent great vessels and adjacent organs. DISCUSSION: Anterior extension may lead to perforation of the visceral peritoneum and spread within the peritoneal cavity. Cytology in peritoneal lavage can be positive before any peritoneal metastasis is seen. Invasion of lymphatics and veins as well as perineural invasion are common. The lymph drainage of the pancreas is multidirectional to superior, inferior, anterior, posterior and left lymph nodes. In node-negative cases, isolated tumor cells in the sinus of regional lymph nodes may be found by immunocytochemistry; such findings must be distinguished from micrometastasis. The same applies to isolated tumor cells in bone marrow. PROGNOSIS: The independent prognostic significance of isolated tumor cells in the regional lymph nodes and in the bone marrow remains to be proven. For classification of anatomic extent the new, fifth edition ( 1997) of the UICC TNM classification should be used. The complex Japanese classification cannot be directly compared with the UICC system. CONCLUSION: Tumor size and histologic grade influence the extent of spread. Anatomic extent and histologic grade are the strongest predictors of outcome.

Adenocarcinoma↗
PubMed1998

Improvements in staging of gastric carcinoma from using the new edition of TNM classification.

AIMS: To recognize possible advantages of the 5th edition of TNM of gastric carcinoma in comparison to the former edition. METHODS: Data from Erlangen Cancer Center for 898 patients with gastric carcinoma treated surgically by total or subtotal gastrectomy with en bloc lymphadenectomy were analysed. RESULTS: The prognostic significance of TNM has been improved by the new edition as demonstrated by the likelihood ratio test. In addition, uncertainties of method in the pathological classification of regional lymph-node metastasis inherent in the 4th edition can now be avoided. CONCLUSION: The changes in the TNM classification introduced by the 5th edition are justified by data from the Erlangen Cancer Center, have methodic advantages in determining the N classification, and lead to an improvement in estimation of outcome.

Adult↗